The proanthocyanidin content as a tool to differentiate between Lotus tenuis and L. corniculatus individuals

► Commercial Lotus tenuis seed stocks usually present contaminations with Lotus corniculatus. ► Described methods for species diagnosis are relatively expensive and time consuming. ► Staining pattern of leaf proanthocyanidins allows the early differentiation between L. tenuis and L. corniculatus. ► This procedure is a workable option to certificate the purity of L. tenuis seed stocks.